package com.yvan.serverless.utils;

import com.google.common.collect.Lists;
import lombok.SneakyThrows;

import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;

public class ReflectUtil {

  /***
   * 获取私有成员变量的值
   */
  @SneakyThrows
  public static Object getValue(Object instance, String fieldName) {

    Field field = instance.getClass().getDeclaredField(fieldName);
    field.setAccessible(true);

    return field.get(instance);
  }

  /**
   * 调用私有成员方法
   */
  @SneakyThrows
  public static Object invoke(Object obj, String methodName, Object... params) {
    int paramCount = params.length;
    Method method;
    Class<?>[] classArray = new Class<?>[paramCount];
    for (int i = 0; i < paramCount; i++) {
      classArray[i] = params[i].getClass();
    }
    method = obj.getClass().getDeclaredMethod(methodName, classArray);
    method.setAccessible(true);
    return method.invoke(obj, params);
  }

  /**
   * 为私有成员变量赋值
   */
  @SneakyThrows
  public static void setValue(Object instance, String fieldName, Object value) {
    Field field = instance.getClass().getDeclaredField(fieldName);
    field.setAccessible(true);

    field.set(instance, value);
  }

  /**
   * 为私有成员变量赋值
   */
  @SneakyThrows
  public static void setValue(Class<?> clazz, Object instance, String fieldName, Object value) {
    Field field = clazz.getDeclaredField(fieldName);
    field.setAccessible(true);

    field.set(instance, value);
  }

  /**
   * 利用反射实现对象之间相同属性复制
   */
  public static void copyProperties(Object source, Object target) throws Exception {

    copyPropertiesExclude(source, target, null);
  }

  /**
   * 复制对象属性
   *
   * @param excludsArray 排除属性列表
   */
  public static void copyPropertiesExclude(Object from, Object to,
      String[] excludsArray) throws Exception {
    List<String> excludesList = null;

    if (excludsArray != null && excludsArray.length > 0) {
      excludesList = Lists.newArrayList(excludsArray);
    }

    Method[] fromMethods = from.getClass().getDeclaredMethods();
    Method[] toMethods = to.getClass().getDeclaredMethods();
    Method fromMethod = null, toMethod = null;
    String fromMethodName = null, toMethodName = null;

    for (int i = 0; i < fromMethods.length; i++) {

      fromMethod = fromMethods[i];
      fromMethodName = fromMethod.getName();

      if (!fromMethodName.contains("get")) {
        continue;
      }
      // 排除列表检测
      if (excludesList != null
          && excludesList.contains(fromMethodName.substring(3)
          .toLowerCase())) {

        continue;
      }
      toMethodName = "set" + fromMethodName.substring(3);
      toMethod = findMethodByName(toMethods, toMethodName);

      if (toMethod == null) {
        continue;
      }
      Object value = fromMethod.invoke(from, new Object[0]);

      if (value == null) {
        continue;
      }
      // 集合类判空处理
      if (value instanceof Collection) {
        Collection<?> newValue = (Collection<?>) value;
        if (newValue.size() <= 0) {
          continue;
        }
      }

      toMethod.invoke(to, new Object[]{value});
    }
  }

  /**
   * 对象属性值复制，仅复制指定名称的属性值
   */
  public static void copyPropertiesInclude(Object from, Object to,
      String[] includsArray) throws Exception {

    List<String> includesList = null;

    if (includsArray != null && includsArray.length > 0) {

      includesList = Arrays.asList(includsArray);

    } else {

      return;
    }
    Method[] fromMethods = from.getClass().getDeclaredMethods();
    Method[] toMethods = to.getClass().getDeclaredMethods();
    Method fromMethod = null, toMethod = null;
    String fromMethodName = null, toMethodName = null;

    for (int i = 0; i < fromMethods.length; i++) {

      fromMethod = fromMethods[i];
      fromMethodName = fromMethod.getName();

      if (!fromMethodName.contains("get")) {
        continue;
      }

      // 排除列表检测
      String str = fromMethodName.substring(3);

      if (!includesList.contains(str.substring(0, 1).toLowerCase()
          + str.substring(1))) {
        continue;
      }

      toMethodName = "set" + fromMethodName.substring(3);
      toMethod = findMethodByName(toMethods, toMethodName);

      if (toMethod == null) {
        continue;
      }

      Object value = fromMethod.invoke(from, new Object[0]);

      if (value == null) {
        continue;
      }

      // 集合类判空处理
      if (value instanceof Collection) {

        Collection<?> newValue = (Collection<?>) value;

        if (newValue.size() <= 0) {
          continue;
        }
      }

      toMethod.invoke(to, new Object[]{value});
    }
  }


  /**
   * 从方法数组中获取指定名称的方法
   */
  public static Method findMethodByName(Method[] methods, String name) {
    for (int j = 0; j < methods.length; j++) {
      if (methods[j].getName().equals(name)) {
        return methods[j];
      }
    }
    return null;
  }
}
